VB.NET – Traversal All text boxes, including text boxes in the group box

For Each c As Control In Me.Controls
 If c.GetType Is GetType(TextBox) Then
 'Do something
 End If
Next

Dim allTxt As New List(Of Control)
For Each txt As TextBox In FindControlRecursive(allTxt, Me, GetType(TextBox ))
'....'
Next

Public Shared Function FindControlRecursive(ByVal list As List(Of Control), ByVal parent As Control, ByVal ctrlType As System.Type ) As List(Of Control)
 If parent Is Nothing Then Return list
 If parent.GetType Is ctrlType Then
 list.Add(parent)
 End If
 For Each child As Control In parent.Controls
 FindControlRecursive(list, child, ctrlType)
 Next
 Return list
End Function

< p>I have several text boxes in winform, some of them are in groupbox. I am trying to loop through all text boxes in my form:

For Each c As Control In Me.Controls
 If c.GetType Is GetType(TextBox) Then
 'Do something
 End If
Next

But it seems to skip Those in the groupbox and Only loop to the other text boxes of the form. So I added another For Each loop to the groupbox text box:

For Each c As Control In GroupBox1.Controls
 If c.GetType Is GetType(TextBox) Then
 'Do something
 End If
Next

I want to know: Is there a way to loop through all the text boxes in the form – Including the text box in the group box – Only one For Each loop? Or a better/more elegant way to do this?

Thanks in advance.

You can use this feature, linq may be a more elegant way.

Dim allTxt As New List(Of Control)
For Each txt As TextBox In FindControlRecursive(allTxt, Me, GetType(TextBox))
'....' 
Next

Public Shared Function FindControlRecursive(ByVal list As List(Of Control), ByVal parent As Control, ByVal ctrlType As System.Type) As List(Of Control)
 If parent Is Nothing Then Return list
 If parent.GetType Is ctrlType Then
 list.Add(parent)
 End If
 For Each child As Control In parent.Controls
 FindControlRecursive(list, child, ctrlType)
 Next
 Return list
End Function